Big dogs, definitely.

1. They're better for your back. You don't have to bend down to pet them!
2. They're easier to walk - you can feel their head at your hip. If you want them to heel you can just hold their head there.
3. Nobody's going to try to hurt you when you've got a big dog at your side.
4. They're just about impossible to trip over.
5. There's just more to love!